#include "HGPnm.h"
#include "../base/HGInc.h"

HGResult HGAPI HGImgFmt_CheckPnmFile(const HGChar* fileName, HGBool* isPnm)
{
	if (NULL == fileName || NULL == isPnm)
	{
		return HGBASE_ERR_INVALIDARG;
	}

	HGPnmLoadInfo info;
	HGResult ret = HGImgFmt_LoadPnmImage(fileName, &info, 0, 0, NULL);
	*isPnm = (HGBASE_ERR_OK == ret ? HGTRUE : HGFALSE);
	return HGBASE_ERR_OK;
}

static HGResult bnm_load_P6(FILE &file, HGPnmLoadInfo* info, HGUInt imgType, HGUInt imgOrigin, HGImage* image)
{
	HGChar c;
	HGInt rgbMaxColor, width, height;

	c = getc(&file);
	while (c == '#')
	{
		while (getc(&file) != '\n');
		c = getc(&file);
	}
	ungetc(c, &file);

	while (c == '\n' || c == '\r' || c == '\t' || c == ' ')
	{
		c = fgetc(&file);
		while (c == '#')
		{
			while (getc(&file) != '\n');
			c = getc(&file);
		}
		
	}
	ungetc(c, &file);

	fscanf(&file, "%d", &width);

	c = getc(&file);
	while (c == '\n' || c == '\r' || c == '\t' || c == ' ')
	{
		c = fgetc(&file);
		while (c == '#')
		{
			while (getc(&file) != '\n');
			c = getc(&file);
		}
	}
	ungetc(c, &file);
	fscanf(&file, "%d", &height);

	if (width <= 0 || height <= 0)
	{
		return HGBASE_ERR_INVALIDARG;
	}

	c = getc(&file);
	while (c == '\n' || c == '\r' || c == '\t' || c == ' ')
	{
		c = fgetc(&file);
		while (c == '#')
		{
			while (getc(&file) != '\n');
			c = getc(&file);
		}
	}
	ungetc(c, &file);

	fscanf(&file, "%d", &rgbMaxColor);

	if (rgbMaxColor <= 0)
	{
		return HGBASE_ERR_INVALIDARG;
	}

	c = fgetc(&file);
	while (c == '\n' || c == '\r' || c == '\t' || c == ' ')
	{
		c = fgetc(&file);
		while (c == '#')
		{
			while (getc(&file) != '\n');
			c = getc(&file);
		}
	}
	ungetc(c, &file);

	_fseeki64(&file, 0, SEEK_CUR);
	uint64_t headerSize = _ftelli64(&file);

	_fseeki64(&file, 0, SEEK_END);
	uint64_t totalSize = _ftelli64(&file);

	if (0 == headerSize || 0 == totalSize)
	{
		fclose(&file);
		return HGBASE_ERR_FAIL;
	}

	size_t dataSize = (size_t)totalSize - (size_t)headerSize;
	uint8_t* buffer = (uint8_t*)malloc(dataSize);
	if (NULL == buffer)
	{
		fclose(&file);
		return HGBASE_ERR_FAIL;
	}

	_fseeki64(&file, headerSize, SEEK_SET);
	size_t readSize = fread(buffer, 1, dataSize, &file);
	if (readSize != dataSize || dataSize != (size_t)width * (size_t)height * 3)
	{
		free(buffer);
		buffer = NULL;
		fclose(&file);
		return HGBASE_ERR_FAIL;
	}

	HGImage image2 = NULL;

	if (info != NULL)
	{
		info->width = width;
		info->height = height;
		info->type = HGIMGFMT_PNMTYPE_RGB_BINRAY;
	}

	if (image != NULL)
	{
		if (imgType == 0)
		{
			imgType = HGBASE_IMGTYPE_RGB;

		}

		HGBase_CreateImage(width, height, HGBASE_IMGTYPE_RGB, HGBASE_IMGORIGIN_TOP, &image2);

		uint8_t* data;
		HGBase_GetImageData(image2, &data);
		HGImageInfo imgInfo;
		HGBase_GetImageInfo(image2, &imgInfo);

		memcpy(data, buffer, dataSize);

		if(HGBASE_ERR_OK != HGBase_CloneImage(image2, imgType, imgOrigin, image))
		{
			return HGBASE_ERR_FAIL;
		}
	}

	HGBase_DestroyImage(image2);
	image2 = NULL;
	free(buffer);
	buffer = NULL;
	fclose(&file);
	return HGBASE_ERR_OK;
}

HGResult HGAPI HGImgFmt_LoadPnmImage(const HGChar* fileName, HGPnmLoadInfo* info,
	HGUInt imgType, HGUInt imgOrigin, HGImage* image)
{
	if (NULL == fileName)
	{
		return HGBASE_ERR_INVALIDARG;
	}

	if (NULL == image)
	{
		if (0 != imgType || 0 != imgOrigin)
		{
			return HGBASE_ERR_INVALIDARG;
		}
	}
	else
	{
		if (0 != imgType && HGBASE_IMGTYPE_BINARY != imgType && HGBASE_IMGTYPE_GRAY != imgType
			&& HGBASE_IMGTYPE_BGR != imgType && HGBASE_IMGTYPE_RGB != imgType
			&& HGBASE_IMGTYPE_BGRA != imgType && HGBASE_IMGTYPE_RGBA != imgType)
		{
			return HGBASE_ERR_INVALIDARG;
		}

		if (HGBASE_IMGORIGIN_TOP != imgOrigin && HGBASE_IMGORIGIN_BOTTOM != imgOrigin)
		{
			return HGBASE_ERR_INVALIDARG;
		}
	}

	FILE* file = fopen(fileName, "rb");
	if (NULL == file)
	{
		return HGBASE_ERR_ACCESSDENIED;
	}

	HGChar header[1024] = {0};
	HGChar c = NULL;

	c = getc(file);
	while (c == '#')
	{
		while (getc(file) != '\n');
		c = getc(file);
	}

	while (c == '\n' || c == '\r' || c == '\t' || c == ' ')
	{
		c = getc(file);
		while (c == '#')
		{
			while (getc(file) != '\n');
			c = getc(file);
		}
	}
	if (c != 'P')
	{
		return HGBASE_ERR_INVALIDDATA;
	}
	else
	{
		c = getc(file);
		if (c < '1' || c > '6')
		{
			return HGBASE_ERR_INVALIDDATA;
		}

		if (c == '6')
		{
			bnm_load_P6(*file, info, imgType, imgOrigin, image);
		}
	}
}

HGResult HGAPI HGImgFmt_SavePnmImage(HGImage image, const HGPnmSaveInfo* info, const HGChar* fileName)
{
	return HGBASE_ERR_OK;
}